Internal-combustion engine



Aug. 12 1924. A 1,504,322

A. P. BRUSH INTERNAL COMBUSTION ENGINE Filedmov. 21 192x Patented Aug. 12, 1924.

UNITED STATES ALANSON P. BRUSH, UF DETROIT, MICHIGAN.

INTERNAL-COMBUSTION ENGINE.

Application filed November To all who-m .at may concern.

Be it known that I,- AnANsoN P. BRUSH, a citizen of the United States of America. residing at Detroit, in the county of Wayne and State ot' Michigan, have invented cer tain new and useful lmprovements in ln termal-Combustion Engines, of which the following is a specication, reference being had therein to the accompanying drawings.

The invention relates to internal comhus tion engines and has for its object the obtaining of greater eiiiciency in the operation of the engine under variable loads. It is Ausual to control internal combustion engines by the throttle, and consequently, to vary the density of the combustible charge which is introduced into the explosion chamber. With certain types vof engines, as, for in-l stance, the Diesel type, the fuel alone is controlled, butit is impractical with small units to employ this principle,vespecially where there 1s to be any great variation in speed range.

One of the reasons why it is practically impossible to control the fuel alone is that to initiate combustion there must be either high massed temperature, or high compression, or a denitely proportioned mixture of the fuel and air adjacent to the ignition point. If. therefore, the quality of the mixture applied hy the carhuretoris Valtered materially from the standard proportions, there is usually a failureof ignition. On the other hand, a mixture of air and fuel, which would not ignite by a spark, may be caused to burn if the temperature ot such mixture can first be raised to'a suilicienily high point, and again. an inert or non-com bustihle gas Within the combustion chamber might be utilized in the development of power could it be 4kept from diluting 'the combustion mixture.V

It is the primary object of the present invention to secu-re at all times a combustible mixture of fuel and air adjacent to the ignition point, such mixture being suici'ent in quantity to operate the engine when idling. It is a further object to vary the quantity of fuel which is introduced into the explosion chamber without materially dimin ishing the quantity of air .so that substan`V tially uniform compression is maintained under varying loads and speeds. Such re# sults I have accomplished by dividing the inlet to the explosion chamber and introducing through one division a combustible' mix- 21. 1921. Serial No. 516,597.

turc of constant proportion, said introduction being:r adjacent to the ignition means, while through the other division air is introdnrecl with a variable amont oi' fuel. The portions of the combustion chamber, with which the divisions of the inlet are respctiivcly connected, are so arranged as to retard conimingling and therefore the uniformly proportioned part will maintain its coml'iustible character adjacent the ignition l point until after ignition. The heat and pressure developed by the ignition of this portion of the charge will he sufficient to cause combustion of the fuel in the leaner mixture. or iii/case only airor inert gas is introduced, this will be utilized expansively in the development of power.

Various specilic constructions may be used for carrying out my inventionand in the drawings'l have illustrated one construction diagrammaticallv. As shown, A is an engine cylinder o conventional type, B the piston therein, C an inlet port shown as arranged in the head communica-ting with the inlet manifold C', and /D the exhaust port communicating' with 'the exhaust manifold D E and l" are respectively the inlet and exhaust valves ivhich are operated by suitably timed mechanism (not shown). G is @the auxiliary 'inlet Which is shown as enter ing the side of thc'cylinder near the end thereof, andV H a fitting adjacent to the i entrance (inwhich provides additional clearance space or an extension of the combustion chamber. I is a carburetor or other source of definitely proportioned combustible mixture of air and fuel. l is a throttle valve for eontrollintY the mixture from the carburetor, and K is au automatic or springclosed checkmalvc which permits the introduction of the charge into the fitting H.' L

' is a spark plug having its electrodes extendingwithin the chamber Il.

i The `rnain inlet C is unprovidcd with a ,Carburetor but has an air entrance orifice M controlled by the check valve N. Ten- "sion is placed on this valve by the spring 0. thc pressure of which ma)r be altered by adjustment of the threaded stom P. Q is a fuel supply conduit connecting with a port ll in the inlet. preferably in thc seat of the valve E. The fuel supply `through this conduit Qis controlled by a. throttle valve S, which is connected by suitable means, such as the rod T, to the throttle J, the arrangement being such that the fuel is only admitted to the port R when the throttle valve-I approaches its open position.

In operation, the suction stroke' of the piston B will draw in a Well proportioned mixture of fuel and air by way of the carvburetor l and fitting H. The inlet valve E will also be opened, but the valve N will remain on its seat until the vacuum in the cylinder will overbalance the resistance of the spring O. As a consequence, there will always be a suliicient uantity of carbureted air to fill the fitting l? or some definite poi-T tion of the combustion' chamber, whilethe remainder of the chamber will be supplied with air through the main inlet C. It the throttle J Vis in the position where the valve S connected therewith is closed, then only air will pass in through the main inlet C. hut if the throttle J is wider opened, auxiliary fuel will pass through the conduit Q to the port R and willbe commingled withthe incoming air. c. It will be obvious that Withlhe construction just described the character of the charge introduced into the explosion chamber is dependent upon a number of factorsg'first, the adjustment or degree of opening of the throttle J; second, the speed of piston displacement; third, the reslstance imposed by the. valve N to the entrance of airthrough the orifice M For example, if the throttle J is nearly closed and the engine is idling, a part of the charge is introduced by way of the carburetor, while a certain amount of uncarbureted air will enter throu h the main inlet C. Under such condition t ere will be sulicient combustible gas in the fitting H `to be ignited by the spark plug L and sufficient power will be generated to operatethe engine without load. If a load is thrown onto the engine, it will be necessary to open the throttle J which, if the engine speed remains the same, will increase the quantity of carburetcd air in proportion to the quantity of uncrbureted air entering the explosion chainber, which will develop greater power.

I f still greater load is thrown onto the engine and the throttle is opened further, the valve S will be opened toadmit 'fuel throu h the port R, which, comrnngling with t e air entering through the inlet C, will increase the power. On the other hand, if the load is decreased, the throttle J will be moved towards its closed ostion, which first will close the valves and cut off the auxiliaryfuel supply. If this does not reduce the piston speed, a further clos of the throttle will increase the quantity dfuncarbureted air entering through the inlet C and will diminish the quantitynof cerbureted air entering the ltting H. us the quantity of fuel will be varied according to load, but without diminishing the compression pressure in the explosion chamber.

The successot' the operation is insured by maintainingjhc proper quality of mixture in the portion of the gas which remains in thoiitting ll, which will insure ignition 4not only of the well proportioned mixture but alsoiot the leanei` mixture. The power developed. however. will he in proportion to the total amount ot fuel introduced and p rcatcr cilicicncy obtained by maintaining suhstantialhY consi ant compression.

lWhat l claim as my invention is: f

l. Au internal con'ilnistion engine comprising a. cylinder, reciprocating piston therein. a combustion chamber at one end of said cylinder. two inlet passages into said` iiile't passage with either pure air or a mixture ofair and ffueL and means whereby the supplyo'f fuel through the latterinjlet passage will come into operation only after the supply of mixture to the other inlet` passage has approached its maximum.

2. An internal combustion engine comprisng la cylinder, a. reciprocating piston therein. a combustion chamber at one end of said cylinder. two inlets into said combustion chamber. means tosupply a substantially uniform combustible mixture through one of other of said inlets. means for also supplying fuel through the other of said inlets. a valve controlling the amount of mixture admitted through said first mentioned inlet. a* aalvc controlling the amount ol liquid fuefjid mittcd through thc other ot said inlets iu`- dependently of the air passing therethrough, and a connection between said valves for obtaining a single control for. theiotal amount of fuel supplied to said cylinder.

3. An internal combustion engine comprising s. cylinder, a reciprocating piston therein. a combustion chamber at one end of Said cylinder, two inlets into said combustion chamber, a. throttle valve controlling one of said inlets, a carburetor connected to said throttle controlled inlet for supplying a substantially uniform combustible mixture, an-

air drag associated with the other of said inlets for admitting air therethrough, means for supplying-liquid fuel to said other inlet, and a valve operated by said throttle valve for varying the amount of lucl supplied through said other inlet independently of the air passing therethrough.

In testimony4 whereof aflix my signature.

ALANSON l. BRUSH.

'saidinlets means to supply air through the w 

